Hi Philip,
> I agree it's mostly just a pathological edge case - if someone declares a
> prefix as the empty string, and then uses that prefix for RDFa data, they
> can't really expect it to work sensibly. But it's quite common in text/html
> documents to have xmlns:* attributes with no value, e.g.:
>
> ...
That's right. There are many features in IE where the mere presence of
a namespace is enough to enable that feature -- i.e., you don't need
to actually have a value for the namespace. Given the number of
examples you've found, I imagine that Microsoft tools must put these
namespaces into the documents automatically.
> ...
>
> It would be nice if these people could use RDFa (e.g. by
> copying-and-pasting CC licensing data), and still have their page handled
> robustly (i.e. still being able to extract the CC data) despite having this
> kind of bogus markup elsewhere in their pages. Fatal errors would be bad
> (they'd make it hard for someone to incrementally adopt RDFa because they'd
> have to fix all these other issues in their markup first), but anything else
> (ignoring the attribute, undeclaring the prefix, treating it as a relative
> URI, etc) seems reasonable to me.
Yes, definitely.
Regards,
Mark
--
Mark Birbeck, webBackplane
mark.birbeck@webBackplane.comhttp://webBackplane.com/mark-birbeck
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